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From: roberts@studguppy.lanl.gov (Doug Roberts)
Newsgroups: comp.ai.shells
Subject: Re: Expert System Complexity
Message-ID: <4662@uklirb.UUCP>
Date: 24 Apr 89 18:48:54 GMT
References: <4638@uklirb.UUCP>
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Organization: Los Alamos National Laboratory
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In-reply-to: rehbold@uklirb's message of 23 Apr 89 17:40:02 GMT
Sorry if duplicates of this appear. inews seems to be reluctant
in accepting this...

In article <4638@uklirb.UUCP> rehbold@uklirb (Robert Rehbold AG Richter) writes:

> In the March issue of the CACM V.E.Barker and D.E.O'Connor give a case study on
> "XCON and beyond". As a characterization of the X... expert systems the
> mention not only the rule counts and type (OPS-5), but also the average number
> of condition and action elements per rule. Moreover they give the average
> number of attributes per condition element and the size and attribute-per-
> object complexity of the database. This description seems sufficient, since
> most readers will know OPS-5 and its expressiveness. Difficulties may arise
> when using not-so-common rule systems or expert systems not mainly based
> on rules, such as model-based systems (i.e. systems that draw their
> conclusions from knowledge of structure, function and behavior).
> 
I believe that the number of objects in an object oriented shell
environment is also an important measure of an expert system's
complexity. Also, some AI shells like KEE (Knowledge Engineering
Environment) allow the use of user written methods (LISP code) within
the body of a rule. Therefore, I feel the following comprises a more
comlete list of the measures of an expert system's complexity:

1. The number of objects being manipulated by the system
2. The number of attributes of each object
3. The number of rules in the system
4. The number of condition and action elements per rule
5. The amount of user written code required to support the application

--Doug
--

===============================================================
Douglas Roberts
Los Alamos National Laboratory
Box 1663, MS F-602
Los Alamos, New Mexico 87545
(505)667-4569
dzzr@lanl.gov
===============================================================